The present invention relates to devices for preventing vehicle batteries from being too depleted when electricity-using features such as headlights or radios are not turned off and are left on after the engine has been shut off. More specifically, the present invention relates to devices that disconnect the electric circuit between the battery and electricity-using components when a change in the electrical properties of the battery corresponding to such circumstances is detected.
In most vehicles, a battery is used to activate a starter motor, which in turn starts the engine. However, if the charge in the battery drops below a certain level, the battery cannot adequately power the starter motor and the vehicle engine will not start as a result.
Such battery failure is frequently caused by the vehicle operator's failure to turn off electricity-using vehicle accessories such as the headlights when the engine is not running.
Accordingly, there is a need for a device that will prevent a vehicle battery from being drained when these accessories are not turned off at the same time as the vehicle engine. There is also a need to be able to reconnect the circuit when the operator returns to the vehicle.